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Home >> Ford >> 2004 >> Taurus SEL, 4D Sedan >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test Hd: Misfire Detection Monitor Through Pinpoint Test HY: Generator/Regulator System - CNG, Flex-Fuel & Gasoline >> Pinpoint Test HH: Exhaust Gas Recirculation System Module (ESM) >> Test Procedure
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Test Procedure

NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION  table of fault code setting condition.
FAULT CODE SETTING CONDITION

Fault Code KOEO KOER Continuous Memory
P0401      HH16
P0402    HH11  HH11
P0403  HH23  HH23  HH23
P0405  HH1  HH1  HH1
P0406  HH4  HH4  HH4
P1400  HH1  HH1  HH1
P1401  HH4  HH4  HH4
P1405    HH29  HH29
P1406  HH31  HH31  HH31
P1408    HH17  
P1409  HH23  HH23  HH23
  1. HH1 DTCS P0405 AND P1400: DETERMINE THE PRESENT DPFEGR PID VOLTAGE 
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.

    Is the voltage less than 0.2 V? 

    Yes No
    GO to  HH2. GO to  HH10.
  2. HH2 INDUCE OPPOSITE DPFEGR SENSOR SIGNAL 
    • Key in OFF position.
    • ESM connector disconnected.
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.

    Is the voltage between 4 V - 6 V? 

    Yes No
    INSTALL a new ESM. GO to  HH3.
  3. HH3 CHECK THE DPFEGR CIRCUIT FOR A SHORT TO SIGRTN OR GND IN THE HARNESS 
    • Key in OFF position.
    • PCM connector disconnected.
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) PCM Connector, Harness Side
      DPFEGR SIGRTN
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) Vehicle Battery
      DPFEGR Negative terminal

    Is the resistance greater than 10K ohms? 

    Yes No
    INSTALL a new PCM. REPAIR the short circuit in question.
  4. HH4 DTCS P0406 AND P1401: DETERMINE THE PRESENT DPFEGR PID VOLTAGE 
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.

    Is the voltage greater than 4 V? 

    Yes No
    GO to  HH5. GO to  HH10.
  5. HH5 CHECK THE VREF VOLTAGE TO ESM 
    • Key in OFF position.
    • ESM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      ( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4 V - 5.5 V? 

    Yes No
    GO to  HH6. REPAIR the open circuit.
  6. HH6 CHECK THE DPFEGR CIRCUIT FOR A SHORT TO POWER 
    • Key in OFF position.
    • PCM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      ( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
      DPFEGR - Pin 5 Negative terminal

    Is the voltage less than 0.2 V? 

    Yes No
    GO to  HH7. REPAIR the short circuit.
  7. HH7 CHECK DPFEGR CIRCUIT FOR SHORT TO VREF 
    • Key in OFF position.
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) PCM Connector, Harness Side
      VREF DPFEGR

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  HH8. REPAIR the short circuit.
  8. HH8 CHECK THE DPFEGR AND SIGRTN CIRCUITS FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) ESM Connector, Harness Side
      DPFEGR DPFEGR - Pin 5
      SIGRTN SIGRTN - Pin 6

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  HH9. REPAIR the open circuit.
  9. HH9 INDUCE THE OPPOSITE DPFEGR SENSOR VOLTAGE 
    • PCM connector connected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A ESM Connector, Harness Side Point B ESM Connector, Harness Side
      DPFEGR - Pin 5 SIGRTN - Pin 6
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.

    Is the voltage less than 0.1 V? 

    Yes No
    INSTALL a new ESM. INSTALL a new PCM.
  10. HH10 PERFORM A THOROUGH WIGGLE TEST ON THE ESM HARNESS 
    • Access the PCM and monitor the DPFEGR PID.
    • Wiggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM.

    Is there any change in the voltage reading, or is a concern found? 

    Yes No
    REPAIR as necessary. Unable to duplicate or identify the fault at this time.
    GO to PINPOINT TEST Z step 1 .
  11. HH11 DTCS P0402 AND P1405: CHECK FOR SIMULTANEOUS PRESENCE 
    NOTE: Diagnose and repair all circuit fault DTCs before diagnosing range/performance or flow concerns. For circuit fault DTC diagnosis, refer to the DIAGNOSTIC TROUBLE CODE (DTC) CHARTS .

    Is DTC P0402 present with DTC P1405? 

    Yes No
    GO to  HH29. GO to  HH12.
  12. HH12 CHECK THE VREF VOLTAGE TO THE ESM 
    • Key in OFF position.
    • ESM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      ( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4.5 V - 5.5 V? 

    Yes No
    GO to  HH13. REPAIR the open circuit.
  13. HH13 SIMULATE THE DPFE SENSOR SIGNAL WITH A VACUUM PUMP 
    • ESM connector connected.
    • Disconnect the downstream DPFE sensor port hose at the ESM.
    • Verify hose and port is clear and free of obstructions.
    • Connect a vacuum pump to the downstream DPFE sensor port.
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.
    • Apply 27 - 30 kPa (8 - 9 in Hg) vacuum to the DPFE sensor and hold for 10 seconds.
    • Quickly release vacuum.
      • The DPFEGR PID voltage must be between 0.2 and 1.3 volt with the key ON and no vacuum applied.
      • The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
      • The DPFEGR PID voltage must decrease to less than 1.5 volts in less than 3 seconds when the vacuum is released.

      Does the DPFEGR PID voltage indicate a fault in the DPFE sensor? 

      Yes No
      INSTALL a new ESM. GO to  HH14.
  14. HH14 INSPECT EVR SOLENOID VENT FOR BLOCKAGE 
    NOTE: When the EGR valve is closed, the EVR solenoid vacuum is vented through the solenoid vent to the atmosphere. A plugged EVR solenoid vent will not allow EGR vacuum to vent to atmosphere.
    • Disconnect the EVR vacuum source hose.
    • Remove the EVR solenoid vent cap (if removable).
    • Remove the filter and inspect for blockage, or in some cases, icing.
    • Connect a hand vacuum pump to EVR vacuum source.
    • Apply 34 to 51 kPa (10 to 15 in Hg) vacuum.

    Does the EVR solenoid vacuum bleed off? 

    Yes No
    GO to  HH15. REPAIR the vent or if not repairable, INSTALL a new ESM.
  15. HH15 CHECK THE EGR VALVE FOR CARBON BUILD-UP 
    • REMOVE the ESM.
    • Visually inspect the EGR valve and valve seat for proper seating, carbon build-up and debris.

    Is a concern present? 

    Yes No
    REPAIR as necessary. Unable to duplicate or identify the fault at this time.
  16. HH16 DTC P0401: PERFORM THE KOER SELF-TEST 
    NOTE: Diagnose and repair all circuit fault DTCs before diagnosing range/performance or flow concerns.
    • Perform the KOER self-test.

    Is DTC P1408 present? 

    Yes No
    GO to  HH17. GO to  HH19.
  17. HH17 KOER DTC P1408: RETRIEVE CONTINUOUS MEMORY DTC 
    NOTE: If any DTC other than P1406 appears, note the DTC and refer to POWERTRAIN DTC CHARTS & DESCRIPTIONS - CNG, FLEX-FUEL & GASOLINE after completing this pinpoint test.
    NOTE: Do NOT replace the ESM if DTCs P0106 and P0400 are in continuous memory. Check the vacuum hose to the MAP sensor and verify proper MAP sensor operation.
    • Retrieve all continuous memory DTCs.

    Is DTC P1405 or P1406 present? 

    Yes No
    For DTC P1405, GO to  HH29.
    For DTC P1406, GO to  HH31.
    GO to  HH18.
  18. HH18 CHECK THE VREF VOLTAGE TO THE ESM 
    • Key in OFF position.
    • ESM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      ( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4.5 V - 5.5 V? 

    Yes No
    GO to  HH19. REPAIR the open circuit.
  19. HH19 CHECK THE EVR SOLENOID VACUUM 
    • ESM connector connected.
    • Disconnect the EVR vacuum source hose.
    • Connect a vacuum gauge to the EVR vacuum source hose.
    • Key on engine running.
    • Monitor the vacuum gauge.

    Is the manifold vacuum greater than 34 kPa (10 in-Hg)? 

    Yes No
    GO to  HH20. REPAIR as necessary.
  20. HH20 SIMULATE THE DPFE SENSOR SIGNAL WITH A VACUUM PUMP 
    • Disconnect the downstream DPFE sensor port hose at the ESM.
    • Verify hose and port is clear and free of obstructions.
    • Connect a vacuum pump to the downstream DPFE sensor port.
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.
    • Apply 27 - 30 kPa (8 - 9 in Hg) vacuum to the DPFE sensor and hold for 10 seconds.
    • Quickly release vacuum.
      • The DPFEGR PID voltage must be between 0.2 and 1.3 volt with the key ON and no vacuum applied.
      • The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
      • The DPFEGR PID voltage must decrease to less than 1.5 volts in less than 3 seconds when the vacuum is released.

      Does the DPFEGR PID voltage indicate a fault in the DPFE sensor? 

      Yes No
      INSTALL a new ESM. Reconnect all hoses.
      GO to  HH21.
  21. HH21 CHECK THE EVR SOLENOID OPERATION 
    • Key on engine running.
    • Engine at normal operating temperature.
    • Allow the engine idle to stabilize.
    • Access the PCM and monitor the RPM PID.
    • Access Output State Control.
    • Increase the EVR duty cycle while monitoring the RPM PID.

    Does the RPM decrease or the engine stall as the EVR duty cycle is increased? 

    Yes No
    Unable to duplicate or identify the fault at this time.
    Check for the presence of carbon build-up in the EGR passage.
    GO to  HH22.
  22. HH22 CHECK FOR THE PRESENCE OF CARBON BUILD-UP IN THE EGR PASSAGE 
    NOTE: In certain vehicle applications, carbon build-up may occur downstream of the ESM. An inspection is required to make sure the passage in the upper intake manifold plenum chamber behind the ESM is open to allow exhaust gas flow.
    • Key in OFF position.
    • Remove the ESM.
    • Disconnect the air inlet tube from the throttle body. For additional information, refer to the appropriate INTAKE AIR DISTRIBUTION & FILTERING article.
    • Prop open the throttle body.
    • Apply regulated shop air to the EGR port at the location where the ESM attaches to the upper intake manifold.

    Is a restriction concern present? 

    Yes No
    CLEAN the EGR port as necessary and reinstall the ESM. INSTALL a new ESM.
  23. HH23 DTCS P0403 AND P1409: CHECK THE EVR SOLENOID OPERATION 
    • Key on engine running.
    • Engine at normal operating temperature.
    • Allow the engine idle to stabilize.
    • Access the PCM and monitor the RPM PID.
    • Access Output State Control.
    • Increase the EVR duty cycle while monitoring the RPM PID.

    Does the RPM decrease or the engine stall as the EVR duty cycle is increased? 

    Yes No
    Unable to duplicate or identify the fault at this time.
    GO to PINPOINT TEST Z step 1 .
    GO to  HH24.
  24. HH24 CHECK THE VPWR VOLTAGE TO THE EVR SOLENOID 
    • Key in OFF position.
    • ESM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      ( + ) ESM Connector, Harness Side ( - ) Vehicle Battery
      VPWR - Pin 4 Negative terminal

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  HH25. REPAIR the open circuit.
  25. HH25 CHECK THE EVR SOLENOID COIL RESISTANCE 
    • Key in OFF position.
    • Measure the resistance between:
      ( + ) ESM Connector, Component Side ( - ) ESM Connector, Component Side
      VPWR - Pin 4 EGRVR - Pin 1

    Is the resistance between 26 ohms - 40 ohms? 

    Yes No
    GO to  HH26. INSTALL a new ESM.
  26. HH26 CHECK THE EVR CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • Measure the resistance between:
      ( + ) ESM Connector, Harness Side ( - ) PCM Connector, Harness Side
      EGRVR - Pin 1 EGRVR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  HH27. REPAIR the open circuit.
  27. HH27 CHECK THE EVR CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
      ( + ) PCM Connector, Harness Side ( - ) Vehicle Battery
      EGRVR Negative terminal

    Is the voltage less than 1 V? 

    Yes No
    GO to  HH28. REPAIR the short circuit.
  28. HH28 CHECK THE EVR CIRCUIT FOR A SHORT TO GND IN THE HARNESS 
    • Key in OFF position.
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - )
      EGRVR Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    INSTALL a new PCM. REPAIR the short circuit.
  29. HH29 DTC P1405: INSPECT THE UPSTREAM PRESSURE HOSE CONNECTION AND ESM ATTACHMENT 
    • Verify the EGR valve is securely attached and exhaust gases are not leaking from the sealing surface.
    • Inspect the upstream DPFE sensor port hose at the ESM for a disconnect or poor connection.

    Is the DPFE sensor hose and the ESM securely attached? 

    Yes No
    GO to  HH30. REPAIR as necessary.
  30. HH30 INSPECT THE UPSTREAM PRESSURE HOSE FOR RESTRICTION 
    NOTE: It is essential that ONLY the correct Ford replacement pressure hose be used. The length of hose must also remain the same for proper system operation.
    • Visually inspect the upstream pressure hose routing. The hose must not be pinched or have dips in it where water could settle or freeze.
    • REMOVE the upstream pressure hose and carefully inspect for plugging, water or leaks.

    Is a fault present? 

    Yes No
    REPAIR or REPLACE the pressure hose as necessary. GO to  HH33.
  31. HH31 DTC P1406: INSPECT THE DOWNSTREAM PRESSURE HOSE CONNECTION AND ESM ATTACHMENT 
    • Verify the EGR valve is securely attached and exhaust gases are not leaking from the sealing surface.
    • Inspect the downstream DPFE sensor hose at the ESM for a disconnect or poor connection.

    Is the DPFE sensor hose and the ESM securely attached? 

    Yes No
    GO to  HH32. REPAIR as necessary.
  32. HH32 INSPECT THE DOWNSTREAM PRESSURE HOSE FOR RESTRICTION 
    NOTE: It is essential that ONLY the correct Ford replacement pressure hose be used. The length of hose must also remain the same for proper system operation.
    • Visually inspect the downstream pressure hose routing.
    • REMOVE the downstream pressure hose and carefully inspect for plugging, water or leaks.

    Is a fault present? 

    Yes No
    REPAIR or REPLACE the pressure hose as necessary. GO to  HH33.
  33. HH33 SIMULATE THE DPFE SENSOR SIGNAL WITH A VACUUM PUMP 
    • Disconnect the downstream DPFE sensor port hose at the ESM.
    • Connect a vacuum pump to the downstream DPFE sensor port.
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.
    • Apply 27 - 30 kPa (8 - 9 in Hg) vacuum to the DPFE sensor and hold for 10 seconds.
    • Quickly release vacuum.
      • The DPFEGR PID voltage must be between 0.2 and 1.3 volt with the key ON and no vacuum applied.
      • The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
      • The DPFEGR PID must drop to less than 1.5 volts in less than 3 seconds when the vacuum is released.

      Does the DPFEGR PID voltage indicate a fault in the DPFE sensor? 

      Yes No
      INSTALL a new ESM. Unable to duplicate or identify the fault at this time.
      GO to PINPOINT TEST Z step 1 .
  34. HH34 EGR DIAGNOSIS BY SYMPTOM: CHECK FOR EGR FLOW WITH THE EVR VACUUM HOSE DISCONNECTED AND PLUGGED 
    NOTE: Perform the KOER self-test.

    REPAIR any other DTCs.

    • Possible causes for EGR flow at idle with no related DTCs:
      • EGR valve not fully seating.
      • EVR solenoid vent restricted.
      • Damaged EVR solenoid.
    • Disconnect and plug the EVR vacuum source hose.
    • Key in ON position.
    • Access the PCM and monitor the DPFEGR PID.
    • Record the PID voltage.
    • Key on engine running.
    • With the engine at idle, observe the DPFEGR PID voltage.
    • Compare to engine OFF voltage.
    • An increase in DPFEGR PID voltage at idle indicates EGR flow.

    Is the idle DPFEGR PID voltage greater than 0.15 volt when compared to the KOEO DPFEGR PID voltage? 

    Yes No
    REMOVE and INSPECT the ESM for signs of contamination, unusual wear, carbon deposits, binding or other damage.
    REPAIR as necessary.
    If no concerns are present, install a new ESM.
    INSPECT the EVR solenoid vent for blockage.
    To continue symptom diagnosis, REFER to STEP 3: NO DTC(S) PRESENT SYMPTOM CHARTS .